Editing Electrical mobility (section)

==Applications==
Electrical mobility is the basis for [[electrostatic precipitation]], used to remove particles from exhaust gases on an industrial scale.  The particles are given a charge by exposing them to ions from an [[electrical discharge]] in the presence of a strong field.  The particles acquire an electrical mobility and are driven by the field to a collecting electrode.

Instruments exist which select particles with a narrow range of electrical mobility, or particles with electrical mobility larger than a predefined value.<ref>{{cite journal | author=E. O. Knutson and K. T. Whitby | title=Aerosol classification by electric mobility: Apparatus, theory, and applications | journal=J. Aerosol Sci. | year=1975 | volume=6 | pages=443–451 | doi=10.1016/0021-8502(75)90060-9 | issue=6| bibcode=1975JAerS...6..443K }}</ref>  The former are generally referred to as "differential mobility analyzers".  The selected mobility is often identified with the diameter of a singly charged spherical particle, thus the "electrical-mobility diameter" becomes a characteristic of the particle, regardless of whether it is actually spherical.

Passing particles of the selected mobility to a detector such as a [[condensation particle counter]] allows the number concentration of particles with the currently selected mobility to be measured. By varying the selected mobility over time, mobility vs concentration data may be obtained. This technique is applied in [[scanning mobility particle sizer]]s.